You might need to update your service incrementally, undeploying no more than N instances at a time:
- Describe the appropriate instance template.
- Set the deployment policy with a non-zero value of
max_unavailable: the maximum number of instances to undeploy at the same time.
- Run a group's update operation.
For example, to update an instance group sequentially by undeploying one instance at a time, set the following parameters in the
... deploy-policy: max_unavailable: 1 max_expansion: 0 ... ...
The group will be updated as follows: